Weight Converter
Free weight converter for ounces, pounds, stone, grams, and kilograms. Instantly convert pounds to kilograms, kg to lbs, stone to pounds, and more.
The quantity you want to convert
Conversion Result
Equivalent In All Units
What Is the Weight Converter?
The Weight Converter is a free online tool for converting between the most common weight (mass) units used around the world: ounces, pounds, and stone from the imperial/US customary system, and grams and kilograms from the metric system. It's useful for everything from checking body weight in different units, to converting recipe ingredients, to figuring out shipping weights.
How to Use the Weight Converter
- Enter the amount you want to convert
- Choose the "From" unit — the unit your original value is in
- Choose the "To" unit — the unit you want to convert to
- Click "Convert Weight" to see the result and a full breakdown across every supported unit
Weight Conversion Factors Used
All conversions route through grams as a common base unit. The exact factors used are:
| Unit | Equivalent in Grams |
|---|---|
| 1 ounce | 28.3495 g |
| 1 pound | 453.592 g |
| 1 stone | 6,350.29 g |
| 1 gram | 1 g |
| 1 kilogram | 1,000 g |
To convert between any two units, the calculator first converts your input to grams, then converts from grams to your target unit — the same reliable two-step approach used across all of our converters.
Worked Example
Suppose you want to convert 1 stone to pounds. First, convert to the base unit: 1 stone × 6,350.29 = 6,350.29 grams. Then convert grams to pounds: 6,350.29 ÷ 453.592 ≈ 14.0 pounds. That matches the well-known fact that 1 stone equals exactly 14 pounds — a good sanity check for the converter's accuracy.
Practical Notes
- Pounds and ounces are the everyday units for body weight and small item weights in the United States.
- Stone is still widely used in the UK and Ireland for body weight, alongside pounds.
- Grams and kilograms are the standard metric units used almost everywhere else, and in science, nutrition labels, and shipping worldwide.
- For very small quantities (like a pinch of an ingredient) or very large ones (like a shipping pallet), the calculator preserves extra decimal precision.
Looking for a different conversion? Try our length converter or temperature converter next.